Diabetes is a chronic disease resulting from deficient insulin secretion by the endocrine pancreas. About 7% of the general population in the Western Hemisphere suffers from diabetes. Of these persons, roughly 90% suffer from Type-2 diabetes while approximately 10% suffer from Type-1. In Type-1 diabetes, patients effectively surrender their endocrine pancreas to autoimmune distraction and so become dependent on daily insulin injections to control blood-glucose-levels. In Type-2 diabetes, on the other hand, the endocrine pancreas gradually fails to satisfy increased insulin demands, thus requiring the patient to compensate with a regime of oral medications or insulin therapy. In the case of either Type-1 or Type-2 diabetes, the failure to properly control glucose levels in the patient may lead to such complications as heart attacks, strokes, blindness, renal failure, and even premature death.
Insulin therapy is the mainstay of Type-1 diabetes management and one of the most widespread treatments in Type-2 diabetes, about 27% of the sufferers of which require insulin. Insulin administration is designed to imitate physiological insulin secretion by introducing two classes of insulin into the patient's body: Long-acting insulin, which fulfills basal metabolic needs; and short-acting insulin (also known as fact-acting insulin), which compensates for sharp elevations in blood-glucose-levels following patient meals. Orchestrating the process of dosing these two types of insulin, in whatever form (e.g., separately or as premixed insulin) involves numerous considerations.
First, patients measure their blood-glucose-levels (using some form of a glucose meter) on average about 3 to 4 times per day. The number of such measurements and the variations therebetween complicates the interpretation of these data, making it difficult to extrapolate trends therefrom that may be employed to better maintain the disease. Second, the complexity of human physiology continuously imposes changes in insulin needs for which frequent insulin dosage regimen adjustments are warranted. Presently, these considerations are handled by a patient's endocrinologist or other healthcare professional during clinic appointments. Unfortunately, these visits are relatively infrequent—occurring once every 3 to 6 months—and of short duration, so that the physician or other healthcare professional is typically only able to review the very latest patient medical data. In consequence, it has been shown that more than 60% of patients control their diabetes at sub-optimal levels, leading to unwanted complications from the disease.
Indeed, one of the major obstacles of diabetes management is the lack of availability of a patient's healthcare professional and the relative infrequency of clinic appointments. Studies have, in fact, established that more frequent insulin dosage regimen adjustments—e.g., every 1 to 2 weeks—improves diabetes control in most patients. Yet as the number of diabetes sufferers continues to expand, it is expected that the possibility of more frequent insulin dosage regimen adjustments via increased clinic visits will, in fact, decrease. And, unfortunately, conventional diabetes treatment solutions do not address this obstacle.
The device most commonly employed in diabetes management is the glucose meter. Such devices come in a variety of forms, although all are characterized by their ability to provide patients near instantaneous readings of their blood-glucose-levels. This additional information can be used to better identify dynamic trends in blood-glucose-levels. However, all conventional glucose meters are designed to be diagnostic tools rather than therapeutic ones. Therefore, by themselves, even state-of-the-art glucose meters do not lead to improved glycemic control.
One conventional solution to the treatment of diabetes is the insulin pump. Insulin pumps are devices that continuously infuse short acting insulin into a patient at a predetermined rate to cover both basal needs and meals. As with manual insulin administration therapy, a healthcare professional sets the pump with the patient's insulin dosage regimen during clinic visits. In addition to their considerable current expense, which prohibits their widespread use by patients with Type-2 diabetes, insulin pumps require frequent adjustment by the physician or other healthcare professional to compensate for the needs of individual patients based upon frequent blood-glucose-level measurements.
An even more recent solution to diabetes treatment seeks to combine an insulin pump and near-continuous glucose monitoring in an effort to create, in effect, an artificial pancreas regulating a patient's blood-glucose-level with infusions of short-acting insulin. According to this solution, real-time patient information is employed to match insulin dosing to the patient's dynamic insulin needs irrespective of any underlying physician-prescribed treatment plan. While such systems address present dosing requirements, they are entirely reactive and not instantaneously effective. In consequence of these drawbacks, such combined systems are not always effective at controlling blood glucose levels. For instance, such combined units cannot forecast unplanned activities, such as exercise, that may excessively lower a patient's blood-glucose level. And when the hypoglycemic condition is detected, the delay in the effectiveness of the insulin occasioned not only by the nature of conventional synthetic insulin but also the sub-dermal delivery of that insulin by conventional pumps results in inefficient correction of the hypoglycemic event.
While the foregoing solutions are beneficial in the management and treatment of diabetes in some patients, or at least hold the promise of being so, there continues to exist the need for means that would cost-effectively improve diabetes control in patients.